The HotSpot Group

The HotSpot group is comprised
of developers involved in the design, implementation, and
maintanence of the HotSpot virtual machine.

Introduction

Below you will find the source code for the Java HotSpot virtual
machine, the best Java virtual machine on the planet.

The HotSpot code base has been worked on by dozens of people,
over the course of 10 years, so far. (That's good and bad.) It's
big. There are nearly 1500 C/C++ header and source files,
comprising almost 250,000 lines of code. In addition to the
expected class loader, bytecode interpreter, and supporting runtime
routines, you get two runtime compilers from bytecode to native
instructions, 3 (or so) garbage collectors, and a set of
high-performance runtime libraries for synchronization, etc.

Here's what you don't get with the source code: the class
libraries that in combination with the virtual machine make a Java
Runtime Environment (JRE) or Java Developers Kit (JDK). You can
download those separately. You also don't get our amazing quality
team that keeps the plane flying even while we work on it. You
don't get our automated testing environment and labs full of fast
machines, slow machines, uniprocessors and big iron, machines with
various operating systems and compilers, etc. You don't get our
performance team, to keep us from regressing. Or our partners and
licensees who help us port and keep our code portable. And you
don't get our zillions of happy (and not so happy) users, who keep
us focused on what matters. If you want in on all of that you'll
have to collaborate with us in the continued development of the
platform.